import requests

# 无参数示例

r = requests.get('https://httpbin.org/get')

# 有参数示例

r = requets.get('http://httpbin.org/get', params=d)

传递URL参数：

    在URL中常见?符号，http://httpbin.org/get?key=val 这种带有?传递关键字参数的方式，requests可以通过params实现。

d = {'k1':'v1', 'k2':'v2', 'k3':None, 'k4':['v4','v5']}

    # 字典中键值为None的键不会被添加到URL中

    # 多个键值中间用&符号连接

    # 键值可是列表 例如'k4'

print(r.url)

执行结果为：http://httpbin.org/get?k1=v1&k2=v2&k4=v4&k4=v5

# 1、基本POST实例

import requests

payload = {'key1': 'value1', 'key2': 'value2'}

ret = requests.post("http://httpbin.org/post", data=payload)

print(ret.text)

# 输出结果

{

  "args": {},

  "data": "",

  "files": {},

  "form": {

    "key1": "value1",

    "key2": "value2"

  },

  "headers": {

    "Accept": "*/*",

    "Accept-Encoding": "gzip, deflate",

    "Connection": "close",

    "Content-Length": "23",

    "Content-Type": "application/x-www-form-urlencoded",

    "Host": "httpbin.org",

    "User-Agent": "python-requests/2.18.4"

  },

  "json": null,

  "origin": "不告诉你这里返回的是你的IP地址",

  "url": "http://httpbin.org/post"

}

# 2、发送请求头和数据实例

import requests

import json

url = 'https://api.github.com/some/endpoint'

payload = {'some': 'data'}

headers = {'content-type': 'application/json'}

ret = requests.post(url, data=json.dumps(payload), headers=headers)

print(ret.text)

print(ret.cookies)

# 输出结果

{"message":"Not Found","documentation_url":"https://developer.github.com/v3"}

<RequestsCookieJar[]>

url = 'https://api.github.com/some/endpoint'

headers = {'user-agent': 'my-app/0.0.1'}

r = requests.get(url, headers=headers)

>>> r = requests.get('http://httpbin.org/get')

>>> r.status_code

200

>>> r.status_code == requests.codes.ok

True

# 如果发送了一个错误请求(一个 4XX 客户端错误，或者 5XX 服务器错误响应)，我们可以通过 Response.raise_for_status() 来抛出异常：

>>> bad_r = requests.get('http://httpbin.org/status/404')

>>> bad_r.status_code

404

>>> bad_r.raise_for_status()

Traceback (most recent call last):

  File "requests/models.py", line 832, in raise_for_status

    raise http_error

requests.exceptions.HTTPError: 404 Client Error

# 但是，由于我们的例子中 r 的 status_code 是 200 ，当我们调用 raise_for_status() 时，得到的是：

>>> r.raise_for_status()

None

>>> r.headers

{

    'content-encoding': 'gzip',

    'transfer-encoding': 'chunked',

    'connection': 'close',

    'server': 'nginx/1.0.4',

    'x-runtime': '148ms',

    'etag': '"e1ca502697e5c9317743dc078f67693f"',

    'content-type': 'application/json'

}

#但是这个字典比较特殊：它是仅为 HTTP 头部而生的。根据 RFC 2616， HTTP 头部是大小写不敏感的。

>>> r.headers['Content-Type']

'application/json'

>>> r.headers.get('content-type')

'application/json'

>>> url = 'http://example.com/some/cookie/setting/url'

>>> r = requests.get(url)

>>> r.cookies['example_cookie_name']

'example_cookie_value'

# 如果想要发送你的cookies到服务器，可以使用cookies参数

>>> url = 'http://httpbin.org/cookies'

>>> cookies = dict(cookies_are='working')

>>> r = requests.get(url, cookies=cookies)

>>> r.text

'{"cookies": {"cookies_are": "working"}}'

# Cookie 的返回对象为 RequestsCookieJar，它的行为和字典类似，但界面更为完整，适合跨域名跨路径使用。你还可以把 Cookie Jar 传到 Requests 中：

>>> jar = requests.cookies.RequestsCookieJar()

>>> jar.set('tasty_cookie', 'yum', domain='httpbin.org', path='/cookies')

>>> jar.set('gross_cookie', 'blech', domain='httpbin.org', path='/elsewhere')

>>> url = 'http://httpbin.org/cookies'

>>> r = requests.get(url, cookies=jar)

>>> r.text

'{"cookies": {"tasty_cookie": "yum"}}'

>>> requests.get('http://github.com', timeout=0.001)

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

requests.exceptions.Timeout: HTTPConnectionPool(host='github.com', port=80): Request timed out. (timeout=0.001)

# 注意事项

    timeout 仅对连接过程有效，与响应体的下载无关。 timeout 并不是整个下载响应的时间限制，而是如果服务器在 timeout 秒内没有应答，

    将会引发一个异常（更精确地说，是在 timeout 秒内没有从基础套接字上接收到任何字节的数据时）

    If no timeout is specified explicitly, requests do not time out.